We propose to investigate the direct actions of the narcotic drug LAAM and its two primary metabolites, N-LAAM and DN-LAAM on brain growth in vivo and in culture. The chick embryo will be the experimental animal for the in vivo studies and dissociated brain cell cultures from chick embryos will be the culture system. Specific studies will include: 1. Accumulation and disappearance of 14C-LAAM and its two metabolites in several brain areas of the chick embryo after injection in vivo. 2. The effects of LAAM, N-LAAM and DN-LAAM given at various doses and at various embryonic ages on the development of enzymes associated with growth; ornithine decarboxylase, choline acetyltransferase and tyrosine hydroxylase. 3. The ontological development of opiate receptor binding in several brain areas of the chick and the effects of these narcotic drugs. Using the dissociated brain cell cultures, we will investigate the direct effects of LAAM, N-LAAM and DN-LAAM on morphological growth (neuronal-glial ratio, number and length of neuronal processes, specific neurons affected) and on the maturational profiles of growth enzymes.